RSC Advances
·
2015
·Vol. 5
·期 96
·78874-78879
·
IF 3.84
Hui-da Wan,Dan Li
A preliminary study on the enzymatic biotransformation of ginsenosides is evaluated. β-Galactosidase from Aspergillus sp. displayed β-glucosidase activity, which was responsible for its ability to transform major ginsenoside Rb1 to rare ginsenoside F2 via ginsenoside Rd. The Rb1 conversion, Rd and F2 yields reached 100%, 80.7% and 14.3% after 60 h at 60 °C, respectively. Ginsenoside Rg3 can be selectively hydrolyzed and only Rh2 was obtained with this β-galactosidase as well. Before hydrolysis, an Rg3 inclusion complex was prepared with hydroxypropyl-β-cyclodextrin (HP-β-CD) to improve the aqueous solubility. The solubility of Rg3 increased 74.6 fold, and the phase solubility curve displayed a typical AL-type, which indicates the formation of a 1 : 1 inclusion complex. Using an enzyme loading of 500 U g−1 Rg3, the highest Rg3 conversion of 90.6% and Rh2 yield of 88.5% were obtained after 24 h at 60 °C. These results indicate that β-galactosidase from Aspergillus sp. could be useful for the mass production of rare ginsenosides.
研究领域:
生物化学
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药学
·
酶学
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DOI
高影响因子
Biomed Research International
·
2022
·
IF 3.246
Aparna Vasudevan,Dinesh Kumar Kesavan,Liang Wu,Zhaoliang Su,Shengjun Wang,Mohan Kumar Ramasamy,Waheeta Hopper,Huaxi Xu
Antibiotic resistance is one of the significant problems globally; there is an increase in resistance with introducing every new class of antibiotics. Further, this has become one of the reasons for arising of new resistance mechanisms in Acinetobacter baumannii. In this study, we have screened natural compounds as a possible inhibitor against the NDM-1 β-lactamase enzyme from A. baumannii using a combination of in silico methods and in vitro evaluation. The database of natural compounds was screened against NDM-1 protein, using Glide docking, followed by QM-polarised ligand docking (QPLD). When the screened hits were validated in vitro, withaferin A and mangiferin had good IC50 values in reducing the activity of NDM-1 enzymes, and their fractional inhibitory concentration index (FICI) was ascertained in combination with imipenem. The withaferin A and mangiferin-NDM-1 docking complexes were analyzed for structural stability by molecular dynamic simulation analysis using GROMACS for 100 ns. The molecular properties of the natural compounds were then calculated using density functional theory (DFT). Withaferin A and mangiferin showed promising inhibitory activity and can be a natural compound candidate inhibitor synergistically used along with carbapenems against NDM-1 producing A. baumannii.
研究领域:
微生物学
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药物化学
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计算生物学
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DOI
PubMed
高影响因子
CHEMOSPHERE
·
2019
·
IF 5.108
Boyin Yan,Zhiquan Liu,Rui Huang,Yongpeng Xu,Dongmei Liu,Wei Wang,Zhiwei Zhao,Fuyi Cui,Wenxin Shi
Cyanobacteria produce a series of secondary metabolites , one of which is beta- N -methylamino- l -alanine (BMAA). BMAA is considered to be the cause of human neurodegeneration. Compared with other cyanotoxins, the role of BMAA in cyanobacteria remains unclear. To investigate this question, six strains of cyanobacteria were cultured and tested in this experiment with an optimized and validated BMAA determination method. The results show that four strains can produce BMAA. The effects of nutrient levels on the production of BMAA by Anabaena sp. FACHB-418 were studied by changing the initial concentrations of nitrate (NaNO 3 ) and phosphate (K 2 HPO 4 ) in mediums. Bound BMAA was detected in all samples and the concentrations were within 50–100 ng/g. Free BMAA was presence when the concentration of nitrogen was lower than 1.7 mg/L (121.43 μM). Free BMAA was released from the dead and ruptured cells during the cell decline period, so dissolved BMAA cannot be detectable in the adaptation and logarithmic periods, but could be abundant in the decline periods. Statistical analyses show that free BMAA concentrations were negatively correlated with nitrogen strongly (p = 2.334 × 10 −10 and r = −0.842), but positively correlated with phosphorus weakly (p = 0.016 and r = 0.405). Moreover, the results of culture experiments indicated that exogenous BMAA could inhibit the growth of cyanobacteria that cannot produce BMAA, and the effect was enhanced as the concentration of exogenous BMAA increased. This phenomenon implies that the production of BMAA may be the stress response by some cyanobacteria to low nitrogen conditions to kill other cyanobacteria, i.e., their competitors.
研究领域:
环境科学
·
毒理学
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DOI
PubMed
高影响因子
FLAVOUR AND FRAGRANCE JOURNAL
·
2016
·Vol. 32
·期 2
·102-111
·
IF 1.693
Zujin Yang,Liyun Huang,Xingdong Yao,Hongbing Ji
Estragole (ES) has multiple biological activities and is widely used in food preservation. However, the applications of ES are limited because of its low water solubility and high volatility nature. In this paper, the β-cyclodextrin (β-CD) inclusion complex of ES was prepared by a co-precipitation method with the aim of enhancing its thermal stability and realize its controlled release. Solubility experiments were performed to evaluate the effect of β-CD on ES aqueous solubility. Release experiments of ES from its inclusion complexes were carried out at different temperatures with a relative humidity (RH) and Avrami's equation was used to analyse the release data. The antimicrobial activity of the free and included ES was also examined. The results indicated that the host–guest interactions played a crucial role in enhancing the properties of ES. The inclusion complex was investigated using physico-chemical techniques such as Fourier transform infrared spectroscopy (FTIR), thermal analysis (TGA and DSC), 1H and 2D nuclear magnetic resonance (NMR). The inclusion processes between β-CD and ES were simulated using the semi-empirical PM3 and ONIOM [B3LYP/6-31g(d):PM3] methods. Copyright © 2016 John Wiley & Sons, Ltd.
研究领域:
食品科学
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药物化学
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分子生物学
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DOI
高影响因子
MOLECULES
·
2020
·Vol. 25
·期 3
·687
·
IF 3.267
Wan-Xia Wu,Zi Liu
A series of new hyperbranched aliphatic poly(β-thioether ester)s were prepared by the enzymatic ring-opening polycondensation of 1,4-oxathiepan-7-one (OTO) and AB2/ABB’ comonomer with acid-labile β-thiopropionate groups. Two kinds of comonomers, methyl 3-((3-hydroxy-2-(hydroxymethyl)propyl)thio)propanoate (HHTP) and methyl 3-((2,3-dihydroxypropyl)thio)propanoate (DHTP), with different primary alcohols and secondary alcohols, were synthesized by thiol–ene click chemistry and thiol-ene Michael addition, respectively. Immobilized lipase B fromCandida antarctica(CALB), Novozym 435, was used as the catalyst. The random copolymers were characterized by1H-NMR,13C-NMR, GPC, TGA, and DSC. All branched copolyesters had high molecular weights over 15,000 Da with narrow polydispersities in the range of 1.75–2.01 and were amorphous polymers. Their degradation properties under acidic conditions were also studied in vitro. The polymeric nanoparticles of hyperbranched poly(β-thioether ester)s were successfully obtained and showed good oxidation-responsive properties, indicating their potential for biomedical applications.Keywords:Novozym 435;poly(β-thioether ester);hyperbranched;acid degradation;oxidation response
研究领域:
高分子化学
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生物材料
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酶催化
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DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2025
·
IF 3.6
Yingnan Dong,Yumeng Jia,Kenan Xu,Xu Sun,Jing Wang,Zhongxiang Shi,Yanchen Liu
In order to expand the multi-scene application of rare earth doped luminescent materials in the field of blue light illumination, a series of Ce 3+ doped Na-β″-Al 2 O 3 phosphors were prepared by solid-state method with Na-β″-Al 2 O 3 as matrix. The crystal structure, micro-morphology, optical properties and thermal stability were investigated systematically. The results show that the activated ion Ce 3+ in the prepared Na-β″-Al 2 O 3 : x Ce 3+ phosphor replaces the Al 3+ (CN = 6) lattice in the crystal, and with a outstanding blue light emission. In addition, the thermal stability of Na-β″-Al 2 O 3 : 0.05Ce 3+ phosphor is analyzed by variable temperature spectrum, and its luminescence intensity at 573K can reach 71.55 % at room temperature. Finally, Na-β″-Al 2 O 3 : 0.05Ce 3+ phosphors are packaged with 330 nm n-UV LED chips to obtain high quality blue LED devices. With its high color rendering index (81.60), low color temperature (2886 K) and good color consistency, it provides a theoretical basis for the application of Na-β″-Al 2 O 3 -based phosphors in blue LED devices, and makes it show great application potential in the field of solid-state blue spectral lighting.
研究领域:
材料科学
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固体化学
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发光材料
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照明工程
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无机功能材料
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产品关联
DOI
高影响因子
FOOD HYDROCOLLOIDS
·
2019
·
IF 5.839
Tao Feng,Mengzhu Shui,Zhongqiu Chen,Haining Zhuang,Wenxin Wang,Yan Yang,Jingsong Zhang,Ran Ye
The mechanism of Hericium Erinaceus β-glucan inhibiting starch digestion has been seldom studied. In this study, the mechanism of inhibited starch digestion was explored in the context of interaction between β-glucans of different molecular weights (Mw) and starch. The rates of starch digestion and glucose release decreased with increased Hericium erinaceus β-glucan ( HEBG ) Mw. HEBG reduced leached amylose but increased peak, minimum and final viscosity. In laser confocal scanning microscopy experiments, HEBG was observed to coat the starch. The mechanisms of HEBG modulating glucose release and starch digestion might be due to increase system viscosity and coat starch. We address the specific mechanisms by which starch granules interact with β-glucan molecules and thus contribute to further applications to develop starchy foods with low predicted Glycemic Index (pGI).
研究领域:
食品科学
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营养学
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产品关联
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2017
·Vol. 130
·期 2
·773-780
·
IF 1.953
Zhang Zishou,Li Mei,Wu Lijun,Zhang Yangfan,Mai Kancheng
Aluminum hydroxide-filled polypropylene composites generally form α-crystal due to the strong heterogenous α-nucleation of filler. In order to utilize β-crystal PP with high toughness to prepare aluminum hydroxide-filled PP composites, the aluminum hydroxide-filled PP composites nucleated by calcium pimelate and PP composites filled by calcium pimelate-supported aluminum hydroxide were fabricated. The crystallization and melting behavior of filled composites were compared by differential scanning calorimetry. The influence of aluminum hydroxide contents on the β-crystal content in the filled PP composites was discussed. It is a novel effective method to prepare aluminum hydroxide-filled β-PP composites with calcium pimelate-nucleated aluminum hydroxide.
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2025
·
IF 1.9
Xinyi Guan,Yufei Wang,Liuxin Yan,Xinyu Jiang,Tong Liu,Jie Song,Chunrui Han
The advancement of functional emulsions and emulsion gels that incorporate natural chemical constituents is a significant area of research. The molecular architecture of natural lecithin is characterized by a combination of hydrophilic and hydrophobic segments, which facilitates its solubility in both aqueous and organic solvents, thereby enhancing its efficacy as an emulsifying agent. The study focused on the structural modification of lecithin by incorporation of natural hard tricyclic diterpene molecules, and the resulting compounds (DDPT) could form oil-in-water emulsions with well-dispersed, regular, rounded droplets in soybean oil. It is noteworthy that stable water-in-oil (W/O) emulsion gels containing 50% dichloromethane can be successfully prepared when the emulsifier concentration exceeds 5 wt%, and the frequency scanning results of the rheological tests show that the energy storage modulus G’ is larger than the loss modulus G". Encapsulation studies involving β-carotene revealed that the emulsions achieved a high encapsulation efficiency of up to 94.7% ± 1.5%. The results indicate that the synergistic interplay between the terpene moiety and lecithin structure in the emulsifier significantly enhances encapsulation of β-carotene. The work presents a viable pathway for a promising avenue for the application of emulsion systems in the encapsulation and stabilization of bioactive compounds.
研究领域:
食品科学
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化学工程
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生物技术
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产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2019
·
IF 7.65
Lu Wang,Yang Kang,Cheng-Yuan Xing,Kun Guo,Xiao-Qin Zhang,Li-Sheng Ding,Sheng Zhang,Bang-Jing Li
Airborne particulate matter (PM) pollution has become a serious environmental problem. Thus, there is a need for the development of air filters with satisfactory overall performance. In this paper, we develop a kind of β-cyclodextrin (β-CD) based air filter with high strength, which has not only high filtration efficiency (about 99%) but also good air permeability (the pressure drop is only 45Pa). Especially after long-term application, the pression drop of β-cyclodextrin based was less than half of the commercial air-filter. Additionally, the material can capture the toxic gasous chemicals (e.g. formaldehyde and SO 2 ). The introduction of β-CD is supposed to be the key factor for improvement of air filter.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2019
·
IF 3.579
Ti Li,Xin Li,Taotao Dai,Peng Hu,Xiaoqin Niu,Chengmei Liu,Jun Chen
Phenolic acids are added to some dairy products as functional ingredients. The molecular interactions between the phenolic acids and milk proteins impacts their functional performance and product quality. In this study, the interactions between a milk protein (β-casein) and a number of phenolic acids was investigated: 3,4-dihydroxybenzoic acid (DA); gallic acid (GA); syringic acid (SA); caffeic acid (CaA); ferulic acid (FA); and, chlorogenic acid (ChA). The structural characteristics of the phenolic acids, such as type, hydroxylation, methylation, and steric hindrance, affected their binding affinity to β-casein. The strength of the binding constant decreased in the following order: CaA > ChA > FA > SA > GA > DA. Cinnamic acid derivatives (CaA, FA, and ChA) exhibited a stronger binding affinity with β-casein than benzoic acid derivatives (DA, GA, and SA). Hydrophobic forces and electrostatic interactions dominated the interactions of β-casein with benzoic acid and cinnamic acid derivatives, respectively. The number of hydroxyl groups on the phenolic acids enhanced their binding ability, while steric hindrance effects reduced their binding ability. The influence of methylation depended on phenolic acid type. After binding with phenolic acids, the conformation of the β-casein changed, with a loss of random coil structure, an increase in α-helix structure, and a decrease in surface hydrophobicity. Furthermore, the presence of β-casein decreased the in vitro antioxidant capacities of the phenolic acids, especially for gallic acid. These findings provide some useful insights into the structure–activity relationships of the interaction between β-casein and phenolic acids.
研究领域:
食品科学
·
生物化学
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产品关联
DOI
PubMed
高影响因子
POSTHARVEST BIOLOGY AND TECHNOLOGY
·
2022
·
IF 6.751
Yonghua Zhang,Qiuli OuYang,Bin Duan,Okwong Oketch Reymick,Yue Chen,Yuanzhen Tan,Xiangrong Zhu,Donglin Su,Gaoyang Li,Nengguo Tao
Green mold, caused by Penicillium digitatum , is the primary postharvest disease in citrus fruit. Trans -2-hexenal was found to exert a considerable inhibitory effect on the mycelial growth of P. digitatum with a minimum fungicidal concentration (MFC) of 0.106 g L −1 . To overcome its hydrophobic restriction, a trans -2-hexenal- β -cyclodextrin inclusion complex ( β -CDIC) was prepared by the saturated aqueous solution method. In vitro assays revealed that the MFC of β -CDIC for P. digitatum mycelial growth was 1.00 g L −1 , and 10.0 g L −1 β -CDIC apparently reduced the incidence of green mold in citrus fruit inoculated with P. digitatum while maintaining fruit quality. The structure of β -CDIC was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), fourier transform-infrared spectroscopy (FT-IR), thermogravimetric (TG), and nuclear magnetic resonance (NMR) analyzes. The results showed that the H-1 proton of trans -2-hexenal correlated with the H-5′ proton of β -cyclodextrin ( β -CD), which was further confirmed by molecular docking analysis. The present study suggests that β -CDIC is a promising candidate for controlling postharvest diseases in citrus fruit.
研究领域:
植物病理学
·
食品科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）